A Giant Kelvin Wave Under Watch in California

I came across something that directly concerns California surfers: a large Kelvin wave is currently crossing the Pacific. To be clear, this is not a surf wave but a massive movement of warm water, driven by the weakening of the trade winds linked to El Niño.

When it reaches the American coast, it can temporarily raise sea level. Scientists generally talk about roughly 15 centimeters, with local values potentially higher. That rise does not create swell by itself.

The risk appears when it combines with spring tides, storms and winter swells. A few extra tens of centimeters can be enough to intensify erosion, and the phenomenon could also reshape sandbanks, changing how reefs, point breaks and beach breaks work.

California is particularly exposed. In recent months, Malibu, Dana Point, Carlsbad and San Clemente have already suffered heavy erosion and swell-related damage. The historical reference remains the 1997–1998 El Niño, which left a lasting mark on the coastline.

The article reminds us that nobody can say the 2026–2027 winter will repeat that scenario. But El Niño, high sea levels and this Kelvin wave are stacking up this year, and what interests me is that the stakes go beyond wave size: it is about how the spots themselves could change.

Source: Surf Session